Bag straightening



BEST AVNLABLE C Nov. 2 1926. 1,605,454

- T. MIDGLEY BAG STRAIGHTENING Filed Jan. 7. 1926 2 6 Y INVENTOR.

.E' 'd 27 7 BY EY.

sEsrAv NLABLE cop;

Patented Nov. 2, 1926.

TnioMAs'MIDdLn 's'r, or ,HAMPDEN, MASSACHUSETTS, ASSIGNOR TO 'rnn FISKRUBBER comrniimmn onroornn FALLS, MASSACHUSETTS, A CORPORATION or MASSA-CHUSET'IS.

This invention relates to a method and an apparatus for straightening ina tire "casing the pressure'ifl'uid tags used "during vulcanization'; IIn -manyinstances I of commercial practice the tires jareprepared for.vulcani- Zati'on' upon some banding *form other thanthe {bagf After ithis F form has been *removed it is} necessary to insert the pressurefluid bagg which is' customarily a hollow annulus of rubber somewhatresembling a very thick inner; 4 tube, eprovid'e'd with "a' si1itablevalve open'ii'ig". Since the; outer diameter: of this bag necessarily1arger-gth n the 1 bead diameter of the tire; it -is'}-necessary to foldthe bag in 'orde'r' to get it into'thef internal 'eavity' of thetire;*"' VV henthe hag-has been inserted these; foldsiimustbe"straightened' out. --If the f o'ldsare not removed uneven stretching ofth'e' tire during vulcanization will result. far s I7am"aware,'such-bags have always beenastraightenedby p'ounding the tire w ithlaheavyiiiallet,-th e natural tendency ofthe bag to I assume a truly roundform being utilized; infthexmoinentary periods of readjustmentfollowin'g the'blows ofthe hammer. This method 'is however, "crude "andwill not thoroughlyremove kinks, from the bag. I have found-that greatlyimproved results, both 'as to. speed of operation and I completeness 'ofreadjustment,' can -be' attained by subjecting the; "bag to progressivetension and flexing as set forth in detail'below. At the 'sam'e' time Iam enabled'by my invention to centralize the bag and tire laterally,.soth'at the inner periphery of the bag will be at" all places concentricwith the (bead edges of the casing.

Briefly stated, my improved method consists, in its preferred form(modifications embodying-the same principle being, however; coveredbythe appended claims), in distortingthe bag and tire into the generalformof an oval or ellipse with the bag under circumferential tension,and in shifting this distortion progressively around the-chm cumferenceof the bagas many times as may be "necessary to accomplish the desiredstraightening. At the same time the bag may be straighteneddaterallyinthe casing by exerting a relative twisting on the bag and tire in thedirection necessary while the'bag is being progressively distorted asdescribed above.

As an'aid-to-a fuller comprehension of my -process, "I have illustratedin the accom- 1311c. STRAIGHTENING.

I Application; filed aiiuar 27,1926. Serial No. 84,221.

panying drawings a machine by which my method may be practiced.Referring to these drawings,

Fig. 1 is a plan View of a machine constructed in accordance with myinvention; Fig. 2:is a similar view showing the parts in anotherposition;

'Fig- 3' is a side elevation of the machine;

Fig. 4 is an enlarged section of the means for holding the bag and t re;

Fig. '5 is a detail, partly broken away, showingthe condition of the airbag in the tire before readjustment; and

' Fig. 6 is a similar view showing the bag in its readjusted condition.

The mach ne is supported in a base 10, having a vertical shaft 11journaled in fixed position therein. A horizontal shaft 12, providedwith a pulley 13 whereby it maybe rotated by a belt 14, is gearedto theshaft 11 at '15. 'A' second vertical shaft 16 is guided towards and awayfrom shaft 11 through a slot 17 inthe top of the base. The piston rod 18of a pneumatic cylinder 19, the piston of which is shown at 20 in Fig.1, is connected to the vertical shaft 16 at 21. By suitable airconnections, controlled by a valve 22 having an operating handle 23, airmay be admitted to one end or the other of the air cylinder, and theshaft 16 moved to- 35 wards or away from the shaft 11.

Each of the vertical shafts carries a device for supporting the air bagand tire casing. These two devices are similar, and a description of onewill suffice. Each device comprises a pair of roller shaped members, thepair on shaft 11 being fixed to the shaft while those on shaft 16 arefree to rotate. Each of the rollers is provided with several operatingsurfaces. At the center of each device is a shouldered portion 24 (Fig.

4) which supports the inner periphery of the air bag a, The two rollersare spaced somewhat, as at 25, to afford space for the valve stem 6 withwhich the bag is fitted. Instead of making the rollers in separatedpairs for this purpose, they may, of course, be formed integrally with adeep groove accomplishing the same purpose.

Adjoining the shouldered portions 2 1 are outwardly extending flanges 26extending between the bag and the tire and preferably shaped to fit thecontour of the side of the bag so as to give it additional centralizingsupport and separate it somewhat from the a pair of rollers adapted tosupport the inner periphery of the bag, flanges on the rollers adaptedto extend between the side of the bag and the casing, and means torotate the rollers.

15. A machine for straightening fluid pressure bags in tire casingswhich com rises a pair of rollers adapted to support t e inner peripheryof the bag, means for separating the rollers to exert tension on thebag, and other surfaces adapted to guide the bead edges of the casingwithout substantial tension.

16. A machine for straightening fluid pressure bags in tire casingswhich comprises means for supporting the inner periphery of the bagunder circumferential tension BEST AVAlLABLE C with at least one sectiondistorted into a curvature of less than normal radius, and means forcausing the successive portions of the ba to assume said distortedcurvature.

17. A machine for straightening fluid pressure bags in tire casingswhich comprises means for supporting the inner periphery of the bagunder circumferential tension with at least one section distorted into acurvature of less than normal radius, means for supporting the beadedges of the casing in lateral alignment with the bag but withoutsubstantial circumferential tension, and means for causing successiveportions of the bag and casing to assume said distorted curvature.

THOMAS MIDGLEY.

